diff options
| author | Kim Phillips <kim.phillips@freescale.com> | 2014-06-02 19:42:58 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-07-08 15:31:26 -0700 |
| commit | 3d713e0e382e6fcfb4bba1501645b66c129ad60b (patch) | |
| tree | 9b47c38f09df44537b163ca18eabc8c979aa1f04 /Documentation | |
| parent | 1cec24c59b4a133fc9c83912996168f511075485 (diff) | |
driver core: platform: add device binding path 'driver_override'
Needed by platform device drivers, such as the upcoming
vfio-platform driver, in order to bypass the existing OF, ACPI,
id_table and name string matches, and successfully be able to be
bound to any device, like so:
echo vfio-platform > /sys/bus/platform/devices/fff51000.ethernet/driver_override
echo fff51000.ethernet > /sys/bus/platform/devices/fff51000.ethernet/driver/unbind
echo fff51000.ethernet > /sys/bus/platform/drivers_probe
This mimics "PCI: Introduce new device binding path using
pci_dev.driver_override", which is an interface enhancement
for more deterministic PCI device binding, e.g., when in the
presence of hotplug.
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-platform | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-platform b/Documentation/ABI/testing/sysfs-bus-platform new file mode 100644 index 000000000000..5172a6124b27 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-platform @@ -0,0 +1,20 @@ +What: /sys/bus/platform/devices/.../driver_override +Date: April 2014 +Contact: Kim Phillips <kim.phillips@freescale.com> +Description: + This file allows the driver for a device to be specified which + will override standard OF, ACPI, ID table, and name matching. + When specified, only a driver with a name matching the value + written to driver_override will have an opportunity to bind + to the device. The override is specified by writing a string + to the driver_override file (echo vfio-platform > \ + driver_override) and may be cleared with an empty string + (echo > driver_override). This returns the device to standard + matching rules binding. Writing to driver_override does not + automatically unbind the device from its current driver or make + any attempt to automatically load the specified driver. If no + driver with a matching name is currently loaded in the kernel, + the device will not bind to any driver. This also allows + devices to opt-out of driver binding using a driver_override + name such as "none". Only a single driver may be specified in + the override, there is no support for parsing delimiters. |